Psoas Compartment Block (PCB) Versus L.A Infiltration and Remifentanil Infusion During EVAR

Overview

Endovascular aneurysm repair (EVAR) was introduced in 1990 for the first time as a minimally invasive procedure instead of the conventional open surgical repair, with the aim to decrease morbidity and mortality . Nowadays EVAR has become an acceptable management for patients with infra-renal aortic aneurysms (AAA) . A lot of anesthetic techniques have been used successfully for EVAR. EVAR requires sedative analgesic medications to achieve an acceptable level of comfort to the patient and cardiorespiratory stability. This is prospective randomized single blinded study of patients presenting with aorto-iliac aneurysm who will undergo EVAR. Patient's demographic data will be assessed, as well as clinical presentation, intraoperative complications. 30 patients undergoing elective EVAR will be included and will be divided equally into 2 groups. First group is the psoas compartment block (PCB) (15 patients): 30 ml of bupivacaine 0.25% will be infused over 3 minutes at the anatomical landmark. Second group is the LA and remifentanil group (LR) (15 patients): lidocaine 5 ml of 2% will be injected subcutaneous as local infiltration then remifentanil infusion with rate 0.03-0.1 μg kg-1 min-1. to achieve visual analog scale (VAS) 3 or less. Vital date will be recorded as baseline then every 5 minutes till the end of the procedure. VAS will be recorded as baseline then every 5 minutes till the end of the procedure. Also stress response which will be measured subjectively as vital data and VAS and objectively as cortisol level in the blood which will be measured as base line and immediate after the end of the procedure.

Anatomical, imaging and clinical studies suggest that psoas compartment block (PCB) which was done at L2-L3 level has a high possibility to include L1-L2 roots, and thus can be suitable for inguinal surgery. In our study, the investigators introduce a modified PCB which will be performed in lateral decubitus by a 120 mm stimulated needle inserted at the junction between the lateral third and the medial two-thirds of a line drawn at L2-L3 interspace, between the interspinous line and a line passing through the posterior superior iliac spine (PSIS), parallel to the interspinous line . If twitching of the anterior thigh area is observed, the needle is moved slight cranially. When twitching of the inguinal field is observed, bupivacaine 0.5% 30 ml, will be injected